TPO and cyclic hematopoiesis: The screening showed that the gene mutation detection rate was 93.33%, and was mainly detected in genes that affect thyroid hormone synthesis, such as DUOX2, TPO, and TG. Previous studies have shown that the detection rate of DUOX2 mutations in children with CH in China is as high as 28%-44%, whereas the detection rate obtained in this study was 44%, suggesting that DUOX2 mutations may be the160 main cause of CH in the Chinese population (22–24).